Ingeniería ISSN Impreso: 1409-2441 ISSN electrónico: 2215-2652

Effect of temperature-time on sterilization process for a jacketed bioreactor system: Application of a Ratkowsky Nonlinear Model


Steam sterilization is a technique widely implemented in different biotechnological processes, among them the growth of microorganisms in bioreactors, which require initial aseptic conditions. In the present paper, it was studied the relationship between the lethality and the death rate of Bacillus cereus grown in 7 liter jacked stirred tank bioreactors was examined, where sugar cane molasses was utilized as the main culture medium. The sterilization process was tested with an industrial autoclave within data loggers in bioreactors, which measure the temperature in the cold point to quantify the accumulated lethality. Through data analysis a contour plot allows a graphical prediction of the microbiological sterilization results in terms of colony forming units (CFU). The case study shows that there is range between 16 and 20 minutes, approaching 123 °C, with a null presence of contaminant microorganisms. The surface chart demonstrates the existing non-linear relationship between the variables temperature and time involved. A positive correlation was observed using Ratkowsky mathematical model with a 0,971 correlation coefficient and the estimated value of α = 11,04 and β = -1,49 for the non-lineal model of parameterization. With these results, it is possible to predict the CFU based on  data. This could provide an interesting base for future sterilization practices and a methodology as a starting point for sterilization trials in industry and save time and costs.
PDF (English)
HTML (English)


Boeck, L. D., J. S. Alford, R. L. Pieper, and F. M. Huber (1989) Interaction of media components during bioreactor sterilization: definition and importance of R0. J. Ind. Microbiol. 4: 247-252.

Graham, H., P. Aman, O. Theander, N. Kolankaya, and C.S. Stewart (1985) Influence of heat sterilization and ammoniation on composition and degradation of straw by pure cultures of rumen bacteria. Anim. Feed Sci. Technol. 12: 195-203.

Munarin, F., S. Bozzini, L. Visai, M. C. Tanzi, and P. Petrini (2013) Sterilization treatments on polysaccharides: Effects and side effects on pectin. Food Hydrocoll. 31: 74-84.

Pfeifer, V. F. and C. Vojnovich (1952) Continuous sterilization of media in biochemical processes. Ind. Eng. Chem. 44: 1940-1946.

Boeck, L. D., R. W. Wetzel, S. C. Burt, F. M. Huber, G. L. Fowler, and J. S. Alford (1988) Sterilization of bioreactor media on the basis of computer calculated thermal input designated as F0. J. Ind. Microbiol. 3: 305-310.

Schneider, P. M. (2014) Evaluation of a new rapid readout biological indicator for use in 132 °C and 135 °C vacuum-assisted steam sterilization cycles. Am. J. Infect. Control. 42: e17-e21.

Levine, S. (1955) Determination of the thermal death rate of bacteria. J. Food Sci. 2: 295-301.

Lau, W. L., J. Reizes, V. Timchenko, S. Kara, and B. Kornfeld (2015) Numerical modelling of an industrial steam-air sterilisation process with experimental validation. Appl. Therm. Eng. 75: 122-134.

Lau, W. L.; J. Reizes, V. Timchenko, S. Kara, and B. Kornfeld (2015) Heat and mass transfer model to predict the operational performance of a steam sterilisation autoclave including products. Int. J. Heat Mass Transf. 90: 800-811.

International Organization for Standardization (2009) ISO/TS 17665-2 Sterilization of health care products - Moist heat - Part 2: Guidance on the application of ISO 17665-1. Geneva, Switzerland.

Boca, B. M., E. Pretorius, R.Gochin, R. Chapoullie, and Z. Apostolides (2002) An overview of the validation approach for moist heat sterilization, part I. Pharm. Technol. 26: 62-70.

Choi, S., C. Cheigh, and M. Chung (2013) Optimization of processing conditions for the sterilization of retorted short-rib patties using the response surface methodology. Meat Sci. 94: 95-104.

Huang, L., C. A. Hwang, and J. Phillips (2011) Evaluating the effect of temperature on microbial growth rate - The Ratkowsky and a Bělehrádek -type models. J. Food Sc. 76: M547-M557.

Noble, P. T. (1992) Modeling transport processes in sterilization-in-place. Biotechnol. Prog. 8: 275-284.

Singh, V., W. Hensler, and R. Fuchs (1989) Optimization of batch fermentor sterilization. Biotechnol. Bioeng. 33: 584-591.

Wood, J. P., P. Lemieux, D. Betancourt, P. Kariher, and N., Griffin (2008) Pilot-scale experimental and theoretical investigations into the thermal destruction of a Bacillus anthracis surrogate embedded in building decontamination residue bundles. Environ. Sci. Technol. 42: 5712-5717.

Ates, M. B., D. Skipnes, T. M. Rode, and O. Lekang (2016) Comparison of spore inactivation with novel agitating retort static retort and combined high pressure-temperature treatments. Food Control. 60: 484-492.

Burghaus, I. and H. Dette (2014) Optimal designs for nonlinear regression models with respect to non-informative priors. J Stat Plan Inference. 154: 12-25.

Zwietering, M. H., J. T. de Koos, B. E. Hasenack, J. C. de Witt, and K. van’t Riet (1991) Modeling of bacterial growth as a function of temperature. Appl. Environ. Microbiol. 57: 1094-1101.

Ratkowsky, D. (1993) Principles of nonlinear regression modeling. J. Ind. Microbiol. 12: 195-199.

Karayannakidis, P. D., E. Apostolidis, and C. M. Lee (2014) Comparison of direct steam injection and steam-jacketed heating in squid protein hydrolysis for energy consumption and hydrolysis performance. LWT - - Food Sci. Technol. 57: 134-140.

Padrón, J. A., J. Fernández, J. Suárez, L. L. Pucheta, G. Limia, L. Carballosa, C. Gandolff, O. Martínez, A. Gómez, and J. Carcache (2001) Determinación del tiempo equivalente acumulado durante los ciclos de esterilización, por vapor saturado, en un fermentador empleado en la producción de vacunas. Vaccimonitor. 10: 1-6.

Sherer, E., R.E. Hannemann, A.E. Rundell, and D. Ramkrishna (2009) Application of stochastic equations of population balances to sterilization processes. Chem. Eng. Sci. 64: 764-774.

Alonso, A. A., A. Arias-Méndez, E. Balsa-Canto, M. R. García, J. I. Molina, C. Vilas, and M. Villafín (2013) Real time optimization for quality control of batch thermal sterilization of prepackaged foods. Food Control. 32: 392–403.

International Organization for Standardization (2006) ISO/TS 17665-1: Sterilization of health care products - Moist heat - Part 1: Requirements for the develoment, validation and routine control of a sterilization process for medical devices. Geneva, Switzerland.

Young, J. H. and W. C. Lasher (1995) Dimensionless parameters as design guidelines for sterilization dead-ended tubes. Biotechnol. Progress. 11: 312-317.

Bakalis S., K. Knoerzer, and P.J. Fryer (2015) Modeling food processing operation. 1st ed., pp 67-93. Woodhead Publishing, ElSevier.

Morales-Blancas, E., D. Pérez, C. Rodríguez, and R. Simpson (2005) Simulation of thermal processing of non-symmetric and irregular-shaped foods vacuum packed in retortable pouches. Presentation at IFT Meeting. July 16-20. New Orleans, USA.

Breu, F., S. Guggenbichler, and J. Wollmann (2007) Thermal Processing of Packaged Foods. Springer US. Boston, USA.

Singh, A. P., A. Singh, and H. S. Ramaswamy (2015) Modification of a static steam retort for evaluating heat transfer under reciprocation agitation thermal processing. J. Food Eng. 153: 63-72.

Simpson R., S. Almonacid, and A. Teixeira (2003) Bigelow's general method revisited: Development of a new calculation technique. J. Food Sci. 68: 1324-1333.

Matser, A. M., B. Krebbers, R. W. Van Den Berg, and P. V. Bartels (2004) Advantages of high pressure sterilisation on quality of food products. Trends Food Sci. Technol. 15: 79-85.

Bungay, H. and P. Hosler (1961) Sterilization of filled fermentors. Ind. Eng. Chem. 53: 746-748.

Bernaerts, K., K. J. Versyck, and J. F. Van Impe (2000) On the design of optimal dynamic experiments for parameter estimation of a Ratkowsky-type growth kinetics at suboptimal temperatures. Int. J. Food Microbiol. 54: 27-38.

Wang, J. and W. Wan (2008) Effect of temperature on fermentative hydrogen production by mixed cultures. Int. J. Hydrogen Energy. 33: 5392-5397.

Luu-Thi, H., T. Grauwet, L.Vervoort, M. Hendrickx, and C. W., Michiels (2014) Kinetic study of Bacillus cereus spore inactivation by high pressure high temperature treatment. Innov Food Sci Emerg Technol. 26: 12-71.

Hariram, U. and R. G. Labbe (2015) Growth and inhibition by spices of growth from spores of enteroxigenic Bacillus Cereus in cooked rice. Food Control. 64: 60-64.

Ratkowsky, D. A. (2002) Some examples of and some problems with, the use of nonlinear logistic regression in predictive food microbiology. Int. J. Food Microbiol. 73: 119-125.



Los datos de descargas todavía no están disponibles.